Hello,
I couldn't get the Window Update for 20H2 to install, so I went the Windows 10 update in place suggestion. It also failed. Here's the setupdiaresults.xml file below. Seems to be related to the boot/reboot process.....
<?xml version="1.0" encoding="utf-16"?>
<SetupDiag xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="https://docs.microsoft.com/en-us/windows/deployment/upgrade/setupdiag">
<Version>1.6.0.0</Version>
<ProfileName>FindAbruptDownlevelFailure</ProfileName>
<ProfileGuid>55882B1A-DA3E-408A-9076-23B22A0472BD</ProfileGuid>
<LogErrorLine>2020-12-18 16:49:28, Error SP Operation failed: Update Boot Code. Error: 0x80004005[gle=0x000000b7]</LogErrorLine>
<FailureData>Error: SetupDiag reports abrupt down-level failure.Last Operation: FinalizeError: 0x80004005 - 0x50016</FailureData>
<FailureData>LogEntry: 2020-12-18 16:49:28, Error SP Operation failed: Update Boot Code. Error: 0x80004005[gle=0x000000b7]</FailureData>
<FailureData>Refer to "https://docs.microsoft.com/en-us/windows/desktop/Debug/system-error-codes" for error information.</FailureData>
<FailureDetails>ErrorCode = 0x80004005, ExCode = 0x50016, Oper = Finalize</FailureDetails>
<SetupPhaseInfo>
<PhaseName>Finalize</PhaseName>
<PhaseStartTime>12/18/2020 4:49:15 PM</PhaseStartTime>
<PhaseEndTime>1/1/0001 12:00:00 AM</PhaseEndTime>
<PhaseTimeDelta>0:00:00:00.0000000</PhaseTimeDelta>
<CompletedSuccessfully>false</CompletedSuccessfully>
</SetupPhaseInfo>
<SetupOperationInfo>
<OperationName>Update Boot Code</OperationName>
<OperationStartTime>12/18/2020 4:49:24 PM</OperationStartTime>
<OperationEndTime>1/1/0001 12:00:00 AM</OperationEndTime>
<OperationTimeDelta>0:00:00:00.0000000</OperationTimeDelta>
<CompletedSuccessfully>false</CompletedSuccessfully>
</SetupOperationInfo>
</SetupDiag>